introduce option for JSON output

Also rename printHomeserverMemberCount option accordingly to fit new
output type.

output/json.go

@@ -0,0 +1,30 @@
+package output
+
+import (
+	"encoding/json"
+	"log"
+	"os"
+
+	"codeberg.org/june64/mrvc/roominfotree"
+)
+
+func PrintJSON(roomInfoTree roominfotree.RoomInfoTree, outputHomeserverMemberCount bool) {
+	if !outputHomeserverMemberCount {
+		for _, roomInfo := range roomInfoTree {
+			for _, maxRoomVersionInfo := range roomInfo.MaxRoomVersions {
+				for _, serverInfo := range maxRoomVersionInfo.Servers {
+					for _, versionInfo := range serverInfo.Versions {
+						versionInfo.Homeservers = nil
+					}
+				}
+			}
+		}
+	}
+
+	json, err := json.Marshal(roomInfoTree)
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	os.Stdout.Write(json)
+}